CN101545760A - Optical transmission spherical surface detector - Google Patents
Optical transmission spherical surface detector Download PDFInfo
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- CN101545760A CN101545760A CN200810024553A CN200810024553A CN101545760A CN 101545760 A CN101545760 A CN 101545760A CN 200810024553 A CN200810024553 A CN 200810024553A CN 200810024553 A CN200810024553 A CN 200810024553A CN 101545760 A CN101545760 A CN 101545760A
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Abstract
The invention discloses an optical transmission spherical surface detector for inspecting the surface shape quality of lens convex-concave spherical surfaces, which is characterized by adopting a spherical surface non-contact interference method to obtain a standard spherical wave of which the curve radius changes continuously in certain range by a standard transmission spherical surface instrument consists of a group of positive lenses so as to achieve the detection of the convex-concave spherical surfaces with different curve radiuses, wherein the relative aperture detection coverage of a detected piece can reach F/0.75 to 11. The optical transmission spherical surface detector has the characteristics of multiple functions, no damage to the surface finishment of a detected spherical surface and high test precision, and overcomes the disadvantage of contact measurement of the prior spherical surface sample plate; and if the optical transmission spherical surface detector is used together with a length-measuring linear scale, a length-measuring interferometer, and the like, the curve radiuses of the spherical surfaces can be measured precisely. The optical transmission spherical surface detector can be extensively applied to the optical manufacturing industry to inspect the surface shape quality of various lens convex-concave spherical surfaces.
Description
Technical field
The present invention relates to a kind of striking rope type optical interferometry device, particularly a kind of optical transmission spherical surface detector that is used for the quality inspection of lens convex-concave sphere face shape.
Background technology
Existing optics processing industry normally adopts template method to the check of lens convex-concave sphere face shape quality, promptly by different testplatees and corresponding tested convex-concave sphere contact, detect by an unaided eye again because the different apertures that surface form deviation occurs come sphere face shape quality is judged.During detection, a radius-of-curvature needs a pair of model of convex-concave, when the model face with after tested sphere contacts, will form equal thickness fringes as the clearance occurring between tested sphere and the model face, what its reflected is aperture and the local aperture of tested sphere with respect to model, require the identification aperture according to GB GB2831-81 then, detect and draw lens convex-concave sphere face shape quality.The problem that this traditional model detection method exists is: 1, because each radius-of-curvature value all needs at least one model, and need the identical convex-concave of radius-of-curvature to model, therefore the face shape of model all has different quality requirementss with radius-of-curvature by grade, so all will there be a large amount of model storehouses in sphere processing producer, caused very high capital assets type cost, and the processing of every pair of model also has certain degree of difficulty; 2, the template method measurement is that model is contacted with tested sphere, belong to contact measurement method, cause the damage of tested spherical face easily, beauty defects such as cut appear, influence the surface smoothness of tested sphere: 3, the data of inspection by template sphere face shape are only to describe with f-number, not only method falls behind, and precision is lower, and the error of model self can't quantitatively be deducted.
Summary of the invention
The object of the invention provides that a kind of check, tool that is applicable to various lens convex-concave sphere face shape quality used more, precision height and the low striking rope type optical transmission spherical surface detector of cost.
The objective of the invention is to be achieved through the following technical solutions, optical transmission spherical surface detector, it is by digital wavefront interferometer, the transmission sphere utensil, interferogram monitor and computing machine are formed, the transmission sphere utensil is positioned on the emitting light path of digital wavefront interferometer, digital wavefront interferometer receives the image that the transmission sphere utensil obtains simultaneously, picture output signal after digital wavefront interferometer is handled connects interferogram monitor and computing machine respectively, the invention is characterized in that the transmission sphere utensil is to be made of 2~4 optics positive lens combinations, the focus of the sphere standard utensil after the combination overlaps with the centre of sphere of end positive lens sphere in the transmission sphere standard utensil; Spherical wave behind transmission sphere standard utensil, the tested convex-concave sphere of normal incidence.
The method that the present invention adopts the sphere noncontact to interfere, produce the spherical wave that surpasses diffraction limit, when this spherical wave transmits in the isotropy uniform dielectric, the corrugated still is a sphere, and radius-of-curvature is all different, is equivalent to the sphere model of different curvature, as long as the F number (inverse of relative aperture) of transmission sphere standard utensil is certain, it just can test the very big convex-concave sphere of radius-of-curvature variation range, has overcome existing sphere model and radius shortcoming one to one.Its concrete principle of work is: by digital wavefront interferometer exit plane ripple, after seeing through transmission sphere standard utensil, outgoing surpasses the standard ball ground roll of diffraction limit, its center of curvature is positive lens spheric curvature center, end in seeing through transmission sphere standard utensil all, also overlap with the center of curvature of tested sphere, end positive lens sphere face shape is as the reference sphere.Through the spherical wave of transmission sphere standard utensil outgoing, the tested sphere of noncontact normal incidence returns the distortion spherical wave that has tested sphere surface form deviation information, interferes with the reference sphere ground roll that end positive lens spheric reflection is returned, and forms interference fringe image.By the image detector that is integrated in digital wavefront interferometer inside image is carried out digitizing, send picture monitor to show and Computer Processing, obtain the three-dimensional wave difference figure and the two-dimentional equal-value map of tested sphere face shape at last.Wherein, the optic path feature is identical before the sphere of end, and lens combination fault in material and light transmission error equal error source belong to the public part of interference system, offset automatically during interference.
The present invention compared with prior art its significant advantage is: the method that (1) the present invention adopts the sphere noncontact to interfere, obtain radius-of-curvature continually varying standard ball ground roll within the specific limits by standard transmission sphere utensil, realization is to the detection of different curvature radius convex-concave sphere, the relative aperture of measured piece detects coverage can reach F/0.75~11, the many usefulness of one tool have overcome the shortcoming that existing sphere template method detects; (2) belong to non-cpntact measurement because transmission sphere standard utensil is measured the error of sphere face shape, can not damage the smooth finish of tested spherical face, overcome the shortcoming of existing sphere model contact measurement; (3) in order to guarantee the stability of the present invention as the standard utensil, the sphere of its end positive lens can be made of the little optical material of expansion coefficient, melt quartz material as optics, select the striking rope type of phase shift digital wavefront interferometer for use as digital wavefront interferometer simultaneously, can make the measuring process robotization, be convenient to implement sphere and definitely check, and the measuring accuracy of sphere face shape is very high, if with supporting uses such as the grating chi of measuring length, length-measuring interferometers, can also accurately measure the radius-of-curvature of sphere.Can be widely used in the optics processing industry check to various lens convex-concave sphere face shape quality.
Concrete structure of the present invention is provided by following drawings and Examples.
Description of drawings
Fig. 1 is the general structure synoptic diagram according to optical transmission spherical surface detector of the present invention.
Fig. 2 is the theory of constitution synoptic diagram of transmission sphere standard utensil [2] in the optical transmission spherical surface detector of the present invention.
Fig. 3 is transmission sphere utensil [2] the composition optical principle synoptic diagram that the present invention uses aspheric surface or diffraction optical element.
Fig. 4 is the light path arrangement synoptic diagram that transmission sphere utensil of the present invention [2] is used to test convex surface.
Fig. 5 is that transmission sphere utensil of the present invention [2] is in conjunction with zero compensation machine interferometry aspheric surface light path arrangement synoptic diagram.
Fig. 6 is the concave spherical surface light path synoptic diagram that transmission sphere utensil of the present invention [2] is used to measure long radius-of-curvature.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
Referring to Fig. 1, the optical transmission spherical surface detector of making according to the present invention, it is by digital wavefront interferometer 1, transmission sphere utensil 2, interferogram monitor 4 and computing machine 5 are formed, digital wavefront interferometer 1 is based on digital wavefront interferometer that the single width interferogram handles or based on the phase shift digital wavefront interferometer of phase-shifting technique, interferogram monitor 4 is used to show the interferogram that reflects tested sphere face shape, computing machine 5 is embedded in digital image collection system and interferogram process software, transmission sphere utensil 2 is positioned on the emitting light path of digital wavefront interferometer 1, it is made of 2~4 optics positive lens combinations, wherein the first optics positive lens 6 in limit adopts biconvex lens or plano-convex lens from left to right, last a slice positive lens 7 adopts good transmission optics material of temperature stability such as optics to melt quartzy the making, sphere is coated with anti-reflection film or is not coated with anti-reflection film, and the focus of whole lens combination overlaps with the end sphere centre of sphere.Lens group focus is a real focus, and the light path scheme is plane wave incident, the outgoing of convergence spherical wave.Distinguish by its F number, a cover transmission sphere standard utensil can cover F/0.75, F/1.5, F/3.3, F/7, F/11.Can be when selecting for use according to the principle of F number<radius of curvature R/measurement bore φ.Transmission sphere standard utensil can be made of sphere, also can form by aspheric surface and sphere, or diffraction optics face and sphere composition, or aspheric surface, diffraction optics face and sphere are formed.It is to determine according to the manufacturing cost that allows and volume, the weight of utensil.As constituting the transmission sphere standard utensil of different F numbers fully with sphere, when the F number below 1.5, adopt 4 spherical lenses to form, see shown in Figure 2; The F number is formed at three spherical lenses of 2.0~5.0 usefulness; Two spherical lenses of several 7.0~11.0 usefulness of F are formed.As using aspheric surface or diffraction optics face and the sphere composition of being convenient to eliminate spherical aberration and high-order spherical aberration, can shorten the weight and volume of lens combination.See shown in Figure 3.Tested sphere 3 is positioned at the focal point F of transmission sphere utensil 2 ' after the outgoing spherical wave on, the center of curvature of tested sphere 3 should overlap with the focus and the end sphere centre of sphere of lens combination, the spherical wave behind sphere standard utensil 2 is answered the tested convex-concave sphere 3 of normal incidence.Combinations thereof mainly is applicable to measures concave spherical surface face shape, and it can by selecting the transmission sphere utensil of suitable F number, realize the detection to it according to the size of tested sphere bore and its radius-of-curvature ratio.
The present invention is when measuring protruding sphere face shape, and tested protruding sphere is to place transmission sphere standard utensil 2 focal point F ' before, see shown in Figure 4, its center of curvature and transmission sphere standard utensil 2 focal point F ' overlap.When measuring protruding sphere and selecting transmission sphere standard utensil for use, owing to need avoid tested convex surface to touch the end sphere of transmission sphere standard utensil, except that the principle that should satisfy F number<radius of curvature R/measurement bore φ, also should satisfy the vertex focal length S of radius of curvature R<transmission sphere standard utensil
F '
The present invention can realize by add zero compensation machine 8 between transmission sphere standard utensil 2 and tested sphere 3 when measuring aspheric surface, sees shown in Figure 5ly, and zero compensation machine 8 can be made up of spherical lens, also can form with binary optical device.During measurement, through penetrating sphere standard utensil 2 outgoing standard ball ground rolls, enter zero compensation machine 8, change into aspherical wavefront, the tested aspheric surface 3 of normal incidence, reflected back corrugated see through zero compensation machine 8 once more, become the director sphere ripple that carries aspheric surface information, interfere with the reference corrugated, obtain containing the interference pattern of aspheric surface quality information.
The present invention is when measuring length radius-of-curvature sphere face shape, transmission sphere standard utensil 2 is for producing the transmission sphere standard utensil of virtual focus, see shown in Figure 6, directional light by digital wavefront interferometer 1 outgoing, change into diverging standard ball ground roll, the tested long radius-of-curvature concave spherical surface 3 of normal incidence, the reflected back light wave with interfere with reference to reflecting light, it is long to have shortened interference cavity, avoids the influence of air turbulence to interferometry.
Claims (8)
1, a kind of optical transmission spherical surface detector, it is by digital wavefront interferometer [1], transmission sphere utensil [2], interferogram monitor [4] and computing machine [5] are formed, transmission sphere utensil [2] is positioned on the emitting light path of digital wavefront interferometer [1], digital wavefront interferometer [1] receives the image that transmission sphere utensil [2] obtains simultaneously, picture output signal after digital wavefront interferometer [1] is handled connects interferogram monitor [4] and computing machine [5] respectively, the invention is characterized in that transmission sphere utensil [2] is to be made of 2~4 optics positive lens combinations, the focus of the sphere standard utensil [2] after the combination overlaps with the centre of sphere of end positive lens [7] sphere in the transmission sphere standard utensil [2]; Spherical wave behind sphere standard utensil [2], the tested convex-concave sphere of normal incidence [3].
2,, it is characterized in that the optics positive lens that constitutes above-mentioned transmission sphere utensil [2] is made up of sphere according to the described optical transmission spherical surface detector of claim 1.
3,, it is characterized in that the optics positive lens that constitutes above-mentioned transmission sphere utensil [2] is made up of aspheric surface and sphere according to the described optical transmission spherical surface detector of claim 1.
4,, it is characterized in that the optics positive lens that constitutes above-mentioned transmission sphere utensil [2] is made up of diffraction optics face and sphere according to the described optical transmission spherical surface detector of claim 1.
5,, it is characterized in that the optics positive lens that constitutes above-mentioned transmission sphere utensil [2] is made up of aspheric surface, diffraction optics face and sphere according to the described optical transmission spherical surface detector of claim 1.
6, according to the described optical transmission spherical surface detector of claim 1~5, the first optics positive lens [6] that it is characterized in that constituting above-mentioned transmission sphere utensil [2] is biconvex lens or plano-convex lens.
7, according to the described optical transmission spherical surface detector of claim 1~5, it is characterized in that the end positive lens [7] that constitutes above-mentioned transmission sphere utensil [2] adopts the little optical material of expansion coefficient to make, sphere is coated with anti-reflection film or is not coated with anti-reflection film.
8, according to the described optical transmission spherical surface detector of claim 6, it is characterized in that the end positive lens [7] that constitutes above-mentioned transmission sphere utensil [2] adopts the little optical material of expansion coefficient to make, sphere is coated with anti-reflection film or is not coated with anti-reflection film.
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Cited By (16)
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CN101900537A (en) * | 2010-08-05 | 2010-12-01 | 中国人民解放军国防科学技术大学 | Detection method and device of three-dimensional sphericity error of global spherical surface of optical sphere part |
CN102168955A (en) * | 2011-05-18 | 2011-08-31 | 中国科学院长春光学精密机械与物理研究所 | Method for detecting curvature radius of optical spherical surface |
CN102607454A (en) * | 2011-02-24 | 2012-07-25 | 南京理工大学 | Optical freeform surface interference detection system |
CN103322939A (en) * | 2013-06-26 | 2013-09-25 | 中国科学院上海光学精密机械研究所 | Wax plate face shape on-line real-time measurement device of annular polisher |
CN103673928A (en) * | 2013-12-21 | 2014-03-26 | 大连宏海新能源发展有限公司 | High-precision measuring device for micro-curvature of optical reflecting mirror |
CN104315973A (en) * | 2014-10-31 | 2015-01-28 | 中国科学院长春光学精密机械与物理研究所 | Dual-wavelength Fizeau laser interferometer standard reference mirror |
CN105423951A (en) * | 2015-12-22 | 2016-03-23 | 中国科学院长春光学精密机械与物理研究所 | Etalon of convex reference surface with long radius of curvature |
CN105572864A (en) * | 2015-12-21 | 2016-05-11 | 中国科学院长春光学精密机械与物理研究所 | Compensator optical system used for ultrahigh-precision convex aspheric surface detection |
CN105588521A (en) * | 2014-11-17 | 2016-05-18 | 中国航空工业第六一八研究所 | Method for measuring radius of spherical reflector |
CN105737763A (en) * | 2014-12-11 | 2016-07-06 | 高瑞 | Spherical mirror curvature radius measurement method based on More stripes |
CN106154362A (en) * | 2015-04-28 | 2016-11-23 | 南京理工大学 | A kind of little F number multi-wavelength standard spherical reference battery of lens |
CN106404354A (en) * | 2016-10-11 | 2017-02-15 | 中国科学院长春光学精密机械与物理研究所 | Device and method for measurement of aspheric compensator transmission wavefront equation |
CN106595529A (en) * | 2016-03-15 | 2017-04-26 | 南京理工大学 | Measurement method and device for large-curvature-radius non-zero-digit interference based on virtual Newton's ring |
CN107121092A (en) * | 2017-05-24 | 2017-09-01 | 西安交通大学 | A kind of system and method for laser interference detection bearing ball face type error |
CN112880982A (en) * | 2021-02-07 | 2021-06-01 | 长光卫星技术有限公司 | Precision machining method and system for large-aperture optical lens |
CN117906913A (en) * | 2023-12-04 | 2024-04-19 | 武汉光谷航天三江激光产业技术研究院有限公司 | Automatic screening device and method for laser load capacity of high-power optical element |
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2008
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Cited By (23)
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CN101900537A (en) * | 2010-08-05 | 2010-12-01 | 中国人民解放军国防科学技术大学 | Detection method and device of three-dimensional sphericity error of global spherical surface of optical sphere part |
CN101900537B (en) * | 2010-08-05 | 2012-06-27 | 中国人民解放军国防科学技术大学 | Detection method and device of three-dimensional sphericity error of global spherical surface of optical sphere part |
CN102607454A (en) * | 2011-02-24 | 2012-07-25 | 南京理工大学 | Optical freeform surface interference detection system |
CN102168955A (en) * | 2011-05-18 | 2011-08-31 | 中国科学院长春光学精密机械与物理研究所 | Method for detecting curvature radius of optical spherical surface |
CN102168955B (en) * | 2011-05-18 | 2012-09-19 | 中国科学院长春光学精密机械与物理研究所 | Method for detecting curvature radius of optical spherical surface |
CN103322939B (en) * | 2013-06-26 | 2016-04-13 | 中国科学院上海光学精密机械研究所 | Annular polishing machine wax disk surface shape On-line sampling system device |
CN103322939A (en) * | 2013-06-26 | 2013-09-25 | 中国科学院上海光学精密机械研究所 | Wax plate face shape on-line real-time measurement device of annular polisher |
CN103673928A (en) * | 2013-12-21 | 2014-03-26 | 大连宏海新能源发展有限公司 | High-precision measuring device for micro-curvature of optical reflecting mirror |
CN104315973A (en) * | 2014-10-31 | 2015-01-28 | 中国科学院长春光学精密机械与物理研究所 | Dual-wavelength Fizeau laser interferometer standard reference mirror |
CN105588521B (en) * | 2014-11-17 | 2020-01-14 | 中国航空工业第六一八研究所 | Method for measuring radius of spherical reflector |
CN105588521A (en) * | 2014-11-17 | 2016-05-18 | 中国航空工业第六一八研究所 | Method for measuring radius of spherical reflector |
CN105737763B (en) * | 2014-12-11 | 2018-03-13 | 高瑞 | A kind of spherical mirror curvature radius measurement method based on Moire fringe |
CN105737763A (en) * | 2014-12-11 | 2016-07-06 | 高瑞 | Spherical mirror curvature radius measurement method based on More stripes |
CN106154362A (en) * | 2015-04-28 | 2016-11-23 | 南京理工大学 | A kind of little F number multi-wavelength standard spherical reference battery of lens |
CN105572864A (en) * | 2015-12-21 | 2016-05-11 | 中国科学院长春光学精密机械与物理研究所 | Compensator optical system used for ultrahigh-precision convex aspheric surface detection |
CN105423951A (en) * | 2015-12-22 | 2016-03-23 | 中国科学院长春光学精密机械与物理研究所 | Etalon of convex reference surface with long radius of curvature |
CN106595529A (en) * | 2016-03-15 | 2017-04-26 | 南京理工大学 | Measurement method and device for large-curvature-radius non-zero-digit interference based on virtual Newton's ring |
CN106595529B (en) * | 2016-03-15 | 2019-04-16 | 南京理工大学 | Larger radius of curvature nonzero digit interferometric method and device based on virtual Newton's ring |
CN106404354A (en) * | 2016-10-11 | 2017-02-15 | 中国科学院长春光学精密机械与物理研究所 | Device and method for measurement of aspheric compensator transmission wavefront equation |
CN107121092A (en) * | 2017-05-24 | 2017-09-01 | 西安交通大学 | A kind of system and method for laser interference detection bearing ball face type error |
CN112880982A (en) * | 2021-02-07 | 2021-06-01 | 长光卫星技术有限公司 | Precision machining method and system for large-aperture optical lens |
CN112880982B (en) * | 2021-02-07 | 2024-04-02 | 长光卫星技术股份有限公司 | Precision machining method and system for large-caliber optical lens |
CN117906913A (en) * | 2023-12-04 | 2024-04-19 | 武汉光谷航天三江激光产业技术研究院有限公司 | Automatic screening device and method for laser load capacity of high-power optical element |
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